# CupCalc — Orthopaedic Calculator

> Orthopaedic Calculator (iPhone/iPad app by Zekko LLC.)

- Source: https://appshunter.io/ios/app/cupcalc/id6761444976 (this page in markdown: same URL + `.md`)
- Developer: [Zekko LLC](https://appshunter.io/developer/1889700014)
- Category: Medical
- Price: Free with in-app purchases
- Age rating: 4+
- Requires: iOS 15.1 · 42 MB
- Languages: American English
- Released: 2026-05-22
- Data updated: 2026-08-23
- User reviews in markdown: https://appshunter.io/ios/app/cupcalc/id6761444976/reviews.md

## What is CupCalc?

CupCalc — Spinopelvic Planning Reference
CupCalc is an educational reference calculator for orthopaedic surgeons and trainees performing total hip arthroplasty. It applies published mathematical formulas to compute mobility-specific acetabular cup targets based on pelvic incidence, sacral slope, and femoral mobility classification.
The calculations in CupCalc are derived entirely from peer-reviewed literature. No proprietary algorithms. No black-box outputs. Every number traces back to a published source — accessible within the app.

What CupCalc calculates:
— Functional anteversion and inclination targets referenced to either the anterior pelvic plane or standing AP radiograph
— Standing and sitting sacral slope with delta sacral slope mobility classification
— Pelvic femoral angle (standing and sitting)
— Anterior pelvic tilt correction for anatomic landmark guidance
— Safe zone plot with CSI thresholds 
— Exportable PDF planning summary with full reference list
Built on the published work of:
Bodner, Dorr, Heckmann, Stefl, Kanawade, Wan, and colleagues whose research established the framework for functional spinopelvic planning in THA.
For Fellows:
CupCalc is free for 12 months for active arthroplasty fellows through the Fellow Access program. Apply within the app — program verification is handled automatically via e-mail.
Privacy:
CupCalc does not collect, store, or transmit protected health information. Do not enter patient-identifying information into any field. Anonymous case labels only.

CupCalc is an educational reference tool intended for use by qualified medical professionals. It performs published mathematical formulas and presents results for independent professional evaluation. It does not provide surgical recommendations, replace clinical judgment, or constitute medical advice. Not a medical device. Not cleared by the FDA. All clinical decisions remain the sole responsibility of the treating surgeon.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| CupCalc Pro | $19.99 | per year |
| CupCalc Express | $12.99 | per year |



## Version history (last 3 releases)

### 1.1.5 — 2026-06-22

CupCalc 1.1.5

- Simplified subscription flow — subscribe directly from Account screen
- Fixed: subscription status now correctly recorded in user profile
- Added: contact support option in Account screen
- Bug fixes and stability improvements

### 1.1.4 — 2026-05-30

"Express Subscription" has been added reducing necessary measurements to 2. Formatting changes for some information boxes have been adjusted. EULA Terms of Use link now available in account tab at all times.

### 1.1.1 — 2026-05-22

No release notes.

## Related topics

[congruenceindexapp](https://appshunter.io/ios/topics/congruenceindexapp) · [femur](https://appshunter.io/ios/topics/femur) · [astrid clausen](https://appshunter.io/ios/topics/astrid-clausen)

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-23.*